Certain beta-glucans are found to exhibit significant physiological activities, e.g. hypoglycemic-, hypocholesterolemic- and antioncotic activities via the cellular immune system. Thus, they have drawn attentions as medicine or material therefor.
Examples of pharmaceutically significant beta-glucans which have a use as antioncotic for malignant tumors are "Pachyman" derived from the fruit body of Poria cocos Wolf, as reported in H. Saito et al., Agricultural and Biological Chemistry, Vol. 32, 1261-1269 (1968); "Lentinan" derived from the fruit body of Lentinus edodes Berk, as reported in T. Sasaki et al., Carbohydrate Research, Vol. 47, pp. 90-104 (1976); "Schizophillan" derived from a culture of Schizophillum commune, as reported by K. Tabata et al., Carbohydrate Research, Vol.89, pp.121-135 (1981); and a beta-glucan derived from the fruit body of Auricularia auricula-judae ("kikurage", an edible mushroom), as reported in A. Misaki et al., Carbohydrate Research, Vol.92, pp.115-129 (1981). These beta-glucans bear in common a backbone structure of beta-1,3-linked D-glucopyranose residues with beta-1,6-linked side chains at some of the C-6 positions, and are used in pharmaceuticals as antioncotic.